Breakthrough could mean the end of food allergies

British scientists believe they have made a vital breakthrough in the battle against deadly food allergies.

A team at the Institute of Food Research (IFR) has identified a molecule that could protect against allergies to foods such as nuts, fish and milk which are becoming an increasing threat.

The findings offer a target for the treatment of food allergies because the molecule could be used to bring allergies under control.

Dr Claudio Nicoletti, who is leading the team at the IFR in Norwich, said: "A food protein can be harmless to one person and lethal to another.

"We have identified the missing molecule that normally keeps immune responses under control."

The experts have found that Interleukin-12 is absent in mice which are bred to be allergic to peanuts, and the results, published in the Journal of Allergy and Clinical Immunology, suggest the molecule normally stops allergies to food developing. In severe cases, people can suffer life-threatening reactions, including anaphylactic shock.

The only way now for sufferers to manage the problem is to avoid certain foods and make sure they have injectable adrenaline at hand in case of emergency. If you have a food allergy it means the immune system responds to a food protein as if it was harmful.

The immune system produces immunoglobulin E (IgE) antibodies, which normally help the body fight parasites. In previous research, Dr Nicoletti found that white blood cells called dendritic cells help the immune system decide on how to respond to foreign molecules.

In the latest research, Dr Nicoletti compared dendritic cells in the gut and in the spleen of allergic and allergy-resistant mice. He found that in the gut of susceptible mice, dendritic cells had stopped producing IL-12.

Dr Nicoletti added: "We have identified a molecule that is very important for the regulation of immune response and for the first time clearly represents a potential target for the therapy of allergy."

David Reading, director of the Anaphylaxis Campaign, said: "Food allergy can place a heavy burden on the families affected. We welcome this research and look forward to further developments."

Symptoms of allergies include swelling and itching, eczema, vomiting, diarrhoea, coughing, wheezing or a runny nose or sore, red and itchy eyes. Some people develop a whole-body allergic reaction called anaphylaxis.

This is a rare but potentially fatal reaction causing swelling, loss of consciousness, low blood pressure and breathing problems.